Experiment with Content-Length

This commit experiments with different encodings for the HTTP request
body.

See #1526
See #1441 (PR)

request.go

@@ -113,7 +113,9 @@ func (r *Request) setBodyReader(body io.Reader) error {
 		switch v := body.(type) {
 		case *strings.Reader:
 			r.ContentLength = int64(v.Len())
-		case *bytes.Buffer:
+		// case *bytes.Buffer:
+		//	r.ContentLength = int64(v.Len())
+		case *bytes.Reader:
 			r.ContentLength = int64(v.Len())
 		}
 	}

request_test.go

@@ -4,7 +4,11 @@
 
 package elastic
 
-import "testing"
+import (
+	"bytes"
+	"strings"
+	"testing"
+)
 
 var testReq *Request // used as a temporary variable to avoid compiler optimizations in tests/benchmarks
 
@@ -25,6 +29,64 @@ func TestRequestSetContentType(t *testing.T) {
 	}
 }
 
+func TestRequestContentLength(t *testing.T) {
+	tests := []struct {
+		Body                interface{}
+		Compress            bool
+		ExpectContentLength bool
+		ContentLength       int64
+	}{
+		{
+			Body:                `{}`,
+			Compress:            false,
+			ExpectContentLength: true,
+			ContentLength:       2,
+		},
+		{
+			Body:                strings.NewReader(`{}`),
+			Compress:            false,
+			ExpectContentLength: true,
+			ContentLength:       2,
+		},
+		{
+			Body:                bytes.NewBuffer([]byte(`{}`)),
+			Compress:            false,
+			ExpectContentLength: true,
+			ContentLength:       2,
+		},
+		{
+			Body:                bytes.NewReader([]byte(`{}`)),
+			Compress:            false,
+			ExpectContentLength: true,
+			ContentLength:       2,
+		},
+	}
+
+	for i, tt := range tests {
+		req, err := NewRequest("POST", "/")
+		if err != nil {
+			t.Fatal(err)
+		}
+		if err := req.SetBody(tt.Body, tt.Compress); err != nil {
+			t.Fatal(err)
+		}
+		if tt.ExpectContentLength {
+			contentLength := req.ContentLength
+			if want, have := tt.ContentLength, contentLength; want != have {
+				t.Fatalf("%d. want Content-Length=%d, have %d", i, want, have)
+			}
+		} else {
+			if want, have := int64(0), req.ContentLength; want != have {
+				t.Fatalf("%d. want Content-Length=%d, have %d", i, want, have)
+			}
+			hdrContentLength := req.Header.Get("Content-Length")
+			if hdrContentLength != "" {
+				t.Fatalf("%d. want no Content-Length, have %q", i, hdrContentLength)
+			}
+		}
+	}
+}
+
 func BenchmarkRequestSetBodyString(b *testing.B) {
 	req, err := NewRequest("GET", "/")
 	if err != nil {
@@ -128,3 +190,35 @@ func BenchmarkRequestSetBodyMapGzip(b *testing.B) {
 	testReq = req
 	b.ReportAllocs()
 }
+
+func BenchmarkRequestSetBodyStringReader(b *testing.B) {
+	req, err := NewRequest("GET", "/")
+	if err != nil {
+		b.Fatal(err)
+	}
+	for i := 0; i < b.N; i++ {
+		body := strings.NewReader(`{"query":{"match_all":{}}}`)
+		err = req.SetBody(body, false)
+		if err != nil {
+			b.Fatal(err)
+		}
+	}
+	testReq = req
+	b.ReportAllocs()
+}
+
+func BenchmarkRequestSetBodyStringReaderGzip(b *testing.B) {
+	req, err := NewRequest("GET", "/")
+	if err != nil {
+		b.Fatal(err)
+	}
+	for i := 0; i < b.N; i++ {
+		body := strings.NewReader(`{"query":{"match_all":{}}}`)
+		err = req.SetBody(body, true)
+		if err != nil {
+			b.Fatal(err)
+		}
+	}
+	testReq = req
+	b.ReportAllocs()
+}